Can an enlarged prostate lead to erection problems? The short answer to your question is, it might. Now for the longer explanation.
A relationship between an enlarged prostate (benign prostatic hyperplasia, BPH) and erectile dysfunction was, at one time, believed to be based on age: the thinking was that the older a man was, the more likely he was to have BPH and erectile dysfunction. However, recent research has suggested BPH and the lower urinary tract symptoms that are characteristic of the disease are associated with an increased chance of experiencing erectile dysfunction.
For example, a study of nearly 4,500 men aged 30 to 80 revealed that a high percentage of men who had lower urinary tract symptoms associated with BPH also had erectile dysfunction, regardless of age. At the same time, the percentage of men without urinary tract symptoms who had erectile dysfunction was much lower, again regardless of age.
Two other large studies support this finding. In one, men with severe urinary tract symptoms were about twice as likely to experience erectile dysfunction, while in a multinational survey of men aged 50 to 80, the increased risk of erectile dysfunction among men who had BPH with associated lower urinary tract symptoms ranged from two fold to 11-fold.
Exactly why an enlarged prostate may lead to erectile dysfunction is not clear. However, one idea concerns involvement of the sympathetic nervous system. It has been suggested the nerve fibers in the sympathetic nervous system send an abnormally high number of signals in these men, which may lead to overactivity of the system (a characteristic of men with BPH and its associated urinary symptoms), which is then associated with erectile problems.